Devices comprising light sources and light blockers are of common general knowledge.
A video device such as a television receiver usually comprises a display for displaying video, and may further comprise a light source for producing ambient light for supporting the video. To direct the ambient light into preferred directions, a light blocker may be used to block the ambient light in non-preferred directions.
A lighting device such as a lamp usually comprises a light source for producing light. To direct the light into preferred directions, a light blocker may be used to block the light in non-preferred directions.
Known light blockers for example absorb the light, which reduces an efficiency of the light source of the device.